The other day, I was at my primary care physician for my annual exam (I passed.). We started with the usual: height, weight, heart rate, and blood pressure. The aide doing all this tried to tell me I was 1/4” under 6’2”. Well, my honeys, let me tell you that I have always, well practically always, been just over 6’2”. My dad was just under 6’2”, and I loved looking down on him.

I really took this personally. Frankly, I felt that the aide didn’t give me sufficient time to stand fully erect - kind of like I feel when doctors listen to me breathe; they get impatient and move the stethoscope beforeI am half done with one full cycle. I need to teach them yogic breathing.

So I had the aide recheck my height. And you know what? He still said I was just under 6’2”, albeit by only 1/8” now. I think it was a test of wills. So I measured myself. And, not surprisingly, I was able to elongate myself up another 1/8” to get back to the magic threshold!

Where am I going with all this, you may ask?

A study out of Norway, published in 2006, followed over 21,000 males and 23,000 females for 11 years. Not surprisingly, they found that there is an increasing amount of shrinkage  with age, starting, in the third decade. Extrapolating from their data, by the age of 70, the average person can be expected to have lost 3 cm. of height; by 80, over 5 cm. (One inch equals 2.54 cm.)

I discussed these data with my primary care physician, in view of the fact that I have lost only 0.6 cm, whereas statistically, I should have lost more like 2.3 cm. by this point in my life. We both felt that yoga was the main reason.

We then discussed the implications of shrinkage with age on interpretations of the body mass index. BMI a ratio of weight divided by height squared, which is to say that height has a bigger impact on BMI than does the weight. Now, it doesn’t take a math major to figure out that BMI will go up as a person loses height with age, even though that person’s weight has not gone up at all.  Therefore, BMI charts should take age into account and accordingly raise thresholds for different categories, such as overweight and obese, in order to factor in average rates of height loss.

My recommendation?

Keep coming to yoga class, and keep your weight stable with plenty of exercise and dietary discretion. Tell your doctor to be patient with you while listening to your breath sounds. And tell the N.A. who is measuring your height to give you enough time to elevate the crown of your head!